OBJECTIVE To analyze clinical features and myopathology changes in muscle fibers, connective tissue, and vessels in 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) antibody-associated myopathies. METHODS Retrospective review of records and myopathologic features of 49 consecutive patients with myopathies and serum HMGCR antibodies. RESULTS Clinical features included onset age from 1...

Desminopathies caused by the mutation in the gene coding for desmin are genetically protein aggregation myopathies. Mitochondrial dysfunction is one of pathological changes in the desminopathies at the earliest stage. The molecular mechanisms of mitochondria dysfunction in desminopathies remain exclusive. VDAC1 regulates mitochondrial uptake across the outer membrane and mitochondrial outer mem...

Age-related skeletal muscle dysfunction is a leading cause of morbidity that affects up to half the population aged 80 or greater. Here we tested the effects of increased mitochondrial antioxidant activity on age-dependent skeletal muscle dysfunction using transgenic mice with targeted overexpression of the human catalase gene to mitochondria (MCat mice). Aged MCat mice exhibited improved volun...

Resveratrol is a natural polyphenolic compound produced by plants under various stress conditions. Resveratrol has been reported to exhibit antioxidant, anti-inflammatory, and anti-proliferative properties in mammalian cells and animal models, and might therefore exert pleiotropic beneficial effects in different pathophysiological states. More recently, resveratrol has also been shown to potent...

An increase in the production of reactive oxygen species occurs with muscle disuse, ischemic cardiomyopathy, and conditions that arise with senescence. The resulting oxidative stress is associated with apoptosis-related myopathies. Recent research has suggested that chronic exercise is protective against mitochondrially mediated programmed cell death. To further investigate this, we compared so...

Antibodies have been raised against synthetic peptides corresponding to several computer-predicted epitopes of three mtDNA-encoded subunits, ND4, ND5 and ND6, of the human respiratory chain NADH dehydrogenase (Complex I). Antibodies were characterized by a sensitive immunoblotting assay using proteins from human skeletal muscle mitochondria and by immunoprecipitation of radio-labeled HeLa cell ...

Mitochondrial oxidative stress is a common feature of skeletal myopathies across multiple conditions; however, the mechanism by which it contributes to skeletal muscle dysfunction remains controversial. Oxidative damage to proteins, lipids, and DNA has received the most attention, yet an important role for reversible redox post-translational modifications (PTMs) in pathophysiology is emerging. ...

Single deletions of mitochondrial DNA (mtDNA) were the first pathogenic mutations to be identified in human mtDNA. In a seminal paper, Holt et al reported the presence of single deletions of the mitochondrial genome in patients presenting with mitochondrial myopathies, and since then, the field has experienced enormous progress. To date, 97 different deletions have been reported in MITOMAP, the...

Purpose of review Necrotizing myopathy exhibits a specific histological pattern, characterized by significant necrosis, with simultaneous muscle fiber regeneration, but without or with little inflammation. This histological pattern may be observed in acquired myopathies but also in muscular dystrophy. Acquired necrotizing myopathy can be secondary to drugs or toxics agents, and if not, autoimmu...

Muscle fiber deterioration resulting in progressive skeletal muscle weakness, heart failure, and respiratory distress occurs in more than 20 inherited myopathies. As discussed in this Review, one of the newly identified myopathies is desminopathy, a disease caused by dysfunctional mutations in desmin, a type III intermediate filament protein, or alphaB-crystallin, a chaperone for desmin. The ra...